The Foz is at the dealer right now with some odd electrical problems (The trunk light doesn't work and had a melted wiring harness. The trunk outlet only has a few volts getting to it and some corrosion, and the OBD-II port has no power.

I know the tech who's working on the car personally since he's one of the long time members of the local scooby club and I trust him that he's not trying to screw me out of money or anything.

He has said that he is not sure, but the BIU is where he would start and the most likely at fault. So, what in the world is it?